103 



from apex to margin ; foramon oval, with a conspicuous 

 tubercle on each side, and widely mai-gined beneath, interior 

 margin enamelled, and above which the shell is undulately 

 striate or subcorrugated to the foraminal margin. Long. 14, 

 Lat. 10, alt. 2t mil. Easily distinguished by its hexagonal 

 markings, in which it differs from any described. This shell 

 was described by H. Crosse, in the Jour, de Conchy, in 1864 

 but the fossil forms are generally thinner and fragile, and 

 more like the variety found near Sydney. 



Emakginula transenna. n.s. Shell thick, small, oblong, 

 subquadrate posteriorly, end slightly produced, conical, high, 

 apex submarginal, smooth, acute, recurved, parallel with the 

 margin, anterior surface ventricose, posterior concave, 

 latticed ; radiating ribs 23, high, between them smaller ones 

 which often in descending give rise to still smaller ; transverse 

 ribs raised, but always more sunk than the radiate, and at all 

 the points of intersection, very projecting granules, interstices 

 very deep and square, fissure slightly longer than width, 

 margin denticulate, straight. Long. 11, Lat. 6, alt. 6. Fissure, 

 Long. Ij mill., Lat. I mill. 



There are many fossil Emarginulas, some descending as low 

 as the Inf. Oolite, though most of them are tertiary. The 

 above description, detailed though it may seem, would apply 

 to many species unless particular attention is paid to the re- 

 lative dimensions. It is very near the existing Arctic (?) E. 

 Jissiira, Lamk., but narrower, and less high in pro])ortion to 

 length. It is not unlike the U. clatJ/ratcpforinis, Eichw. 

 (Vienna Miocene) but that has a sinuous margin, and the 

 apex is incurved and marginal. I doubt very much if our 

 fossil is distinct from what Mr. Angas names jE". dilecta of 

 South Australia and N. S. Wales, but which is very distinct 

 from ^. J//ee/« of A. Adams (Proc. Zool. Soc. 1851, p. 85), 

 which comes from King George's Sound. The latter is very 

 dej)ressed with deep fissure. 



Pleurotoma. This genus, which is very largely repre- 

 sented in the tertiary deposits of Europe, and in the existing 

 fauna is not numerically a large genus in Australian or New 

 Zealand tertiaries, and in this it accords with the existing 

 state of things. Out of over 400 living species (divided into 

 many genera and subgenera) Australia has scarcely 30, and 

 out of nearly 400 fossil species the tertiary beds of Australia 

 and New Zealand have not so far yielded a dozen well defined. 

 The genus is mainly characterised by the deep cut or sinus in 

 the outer lip. In this and in the form of the shell there is 

 every variety. I draw attention to two important charac- 

 ters which distinguish the shin.'}, which seems of value in 

 the identification of species. Sometimes it is close to the 



